Neither Council, its committees or members, nor the Mayor, shall direct or request the Manager to make the appointment of any person to, or suspension or removal from, office or employment by the Manager, or in any manner take part in the appointment, discipline, or removal of subordinates and employees in the service of the City. Council, its committees and members, shall deal with that portion of the service of the City for which the Manager is responsible solely through the Manager, and neither Council nor its committees or members, shall give any orders to any subordinate in office. Council may, however, inquire into the conduct of any office or department, the performance of any contract, or any of the affairs of the City, and may, in the exercise of such power, compel or authorize one of its committees to compel the attendance and testimony of witnesses and the production of books, records, papers, and other evidence under penalty of law.